Polyols are compounds containing more than one hydroxyl group, each attached to separate carbon atoms of an aliphatic skeleton. Glycerin is one example of a polyol. Glycerin is a colorless, odorless, viscous liquid that is sweet-tasting and of low toxicity. Also known as glycerol, glycerine, or by its IUPAC name propane-1,2,3-triol, it is a chemical compound with various uses, including as a non-active ingredient in pharmaceutical formulations, as an additive to foods, and as a feedstock for the production of nitroglycerin.
In the past, glycerin was produced synthetically from epichlorohydrin. However, since glycerin forms the backbone of triglycerides, it is produced during transesterification of triglycerides, such as during the production of biodiesel fuel. Because production of biodiesel fuel has increased greatly in the recent past, the supply of glycerin has vastly exceeded demand, turning it into a very low value byproduct. In fact, the value of glycerin is so low that some plants producing it as a by-product have simply been incinerating it. Disposal of glycerin is likely to become an even bigger problem since forecasts suggest that production of biodiesel will continue to increase dramatically.
For at least these reasons, a need exists for new methods of utilizing polyols such as glycerin for producing higher value added products.